A PD-cycler is described in our international patent application published under number WO 95/20985. This PD-cycler is arranged between a source of PD-fluid and a PD patient. The patient has a catheter implanted, which extends from the abdominal cavity inside the patient's peritoneal membrane and through the skin to a catheter coupling located outside the body. The PD-cycler may fill and drain PD-fluid by means of the catheter to and from the patient's peritoneal cavity in order to carry out peritoneal dialysis.
With the form of treatment which is most prevailing nowadays, namely CAPD, Continuous Automated Peritoneal Dialysis, the patient connects the catheter coupling to a tube set which includes a supply bag for PD-fluid and a drain bag. Valves and/or clamps arranged on the tube set are configured so that the patient can drain the contents of the peritoneal cavity into the drain bag, by placing the drain bag on the ground and allowing the fluid to run out with the aid of gravitational force. After that, the valves and/or the tube clamps are configured so that fresh PD-fluid can be filled into the peritoneal cavity from the supply bag, which is positioned in a high position on a stand, by the aid of gravitational force. Then, the patient keeps the PD-fluid in the peritoneal cavity for about 4 hours, after which time a new fill phase takes place. During the night, no fill and drain takes place, and instead one and the same PD-fluid is kept during the whole night, or, alternatively, the peritoneal cavity is drained from PD-fluid.
With the aid of the aforementioned PD-cycler, the replacement can be automated so that no manual action is required apart from the initial connection and final disconnection, which means that the PD-fluid exchanges can take place during the night when the patient is sleeping.
The PD-cycler is normally used for APD which preferably takes place at night, with the patient constantly connected to the PD-cycler. With this form of treatment the patient is completely free during the day. In order to increase the effectiveness, the patient may, however, do one or more fluid exchanges during the day. The treatment form APD is normally more effective than CAPD, inter alia because a larger amount of PD-fluid may be used. The PD-cycler can also be used for any of the currently known peritoneal dialysis treatment methods.
The PD-cycler which is described in the aforementioned WO 95/20985 constitutes an effective solution to the task of carrying out peritoneal dialysis and in particular APD. One disadvantage with this arrangement is however that the tube set which is used has to be placed on the PD-cycler so that the tubes pass through electromagnetically controlled valves which control the operation. There is a risk that the patient will place the tubes so that they pass through the wrong clamps by turning the tube set incorrectly, with the consequent risk of an incorrect treatment.
Normally this problem is solved by using some type of “organizer” which systematises the tubes and may include valve functions. Such a device is disclosed in WO 94/20154, where this organizer consists of a separate plastic unit, to which unit a number of tubes are connected. The unit is placed in a separate holder in the PD-cycler and electromagnetically controlled actuation devices act on valves and membranes included in the unit for producing valve functions and pump functions. The disadvantage of these organizers is that they are often very complicated and thus expensive to manufacture.